By2 2nd june 2014 unofficial mark scheme Watch

Poll: what mark do you think you got in this paper?
65+ (3)
13.04%
63-64 (1)
4.35%
61-62 (1)
4.35%
59-60 (2)
8.7%
57-58 (2)
8.7%
55-56 (2)
8.7%
53-54 (1)
4.35%
51-52 (1)
4.35%
49-50 (1)
4.35%
47-48 (0)
0%
45-46 (3)
13.04%
43-44 (3)
13.04%
41-42 (1)
4.35%
40 or below (2)
8.7%
Mutmit287
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#1
BY2 2ND JUNE 2014 UNOFFICIAL MARK SCHEME
I have tried to create a mark scheme similar to ones you would find on exam papers showing you what you usually (and in the past) have got marks for.
This is not set in stone and some of my answers may be incorrect and that is open to discussion, any corrections would be taken willingly, but remember I am just a student like you, I sat this exam for the first time today!
IMPORTANT:
· Words in brackets are not required for the mark
· Words in bold must be present for the mark to be awarded
· the marks for each question will be shown inside [] after each question
· the marks for individual parts of each question will be shown inside () after the marking point has been addressed
· Answers separated by a / mean that either of the words shown are appropriate for the mark
Question 1
a) A = capillaries/capillary network (1 MARK)
B = Epithelial cells/epithelium cells (1 MARK)
C = Lacteal (1 MARK)
[3 marks]
b) (Large/extensive) capillary network inside the villus (1 MARK) (as the products are continually being carried away) creating a large maintained concentration gradient for diffusion of digested substances (1 MARK)
Projections/microvilli from the epithelial cells (1 MARK) Increases the surface area of the villus allowing a greater surface for diffusion of digested substances (1 MARK)
[4 marks]
c) Mucus (1 MARK)
[1 mark]
d) ANY TWO OF: Lubricates the Gut/Traps microorganisms/prevents or protects the gut wall from being digested by digestive enzymes.
[2 marks]
e) The smooth muscle layer contains the (antagonistic pair) of circular and longitudinal muscle (1 MARK) The circular muscle and the longitudinal muscle contract (at different times to eachother) (1 MARK) pushing the digested molecules/bolus along the gut by peristalsis (1 MARK)
[3 marks]
f) An amine group/NH2 is removed from the amino acid (1 MARK) the amine group is converted to urea and the remainder stored as carbohydrate (1 MARK)
[2 marks]
Total for question 1 [15 marks]
Question 2
a) Transpiration is the loss off/diffusion of water vapour (1 MARK) out of the leaf via/through the stomatal pores (into the atmosphere) (1 MARK)
[2 marks]
b) To maintain a transpiration stream (to absorb water into the roots and pull water up the xylem) (1 MARK)
[1 mark]
c) To prevent air from entered the vessels in the leafy shoot (1 MARK) which would have affected the results (1 MARK)
[2 marks]
d) Measure the distance travelled by the air bubble (1 MARK) in a given amount of time (1 MARK)
[2 marks]
e) Xerophyte (1 MARK)
f) Sunken stomata Trap a humid layer of air on the outside of the stomata (1 MARK) which decreases the water potential gradient (1 MARK) preventing more water vapour from exiting the stomata by transpiration (1 MARK)
[3 marks]
g) ANY TWO FROM: Thick cuticle prevents excessive water loss by transpiration/hairs to trap water vapour and decrease the water potential gradient/rolled leaves to reduce the surface area from which transpiration can occur
[2 marks]
Total for question 2 [13 marks]
Question 3
a)Adaptive radiation (1 MARK)
[1 mark]
b)Natural selection shows that there is variation in all species (1 MARK) and that the individuals in a population will compete for food (1 MARK) the better adapted finches with the beak that is suited to that food source will be able to obtain food and survive wheras the less well adapted finches will die (1 MARK) The finches with the well adapted beaks go on to reproduce and create offspring with the same desirable beaks (1 MARK)
[4 marks]
*this question has been highly debated among students as it was very confusing, In the textbook it states that adaptive radiation is the mechanism for natural selection, so natural selection in the context of the birds was what I and most other have gone on to describe as that was the logical answer, whether this is correct or not I don’t know*
c) The more amino acids that two species have in common the more closely related they are (1 MARK) the gorilla and the human have the most number of amino acids in common and thus they are more closely related (1 MARK) than the human and the horse who have less amino acids and common and so are less closely related (1 MARK)
[3 marks]
d) Amino acid sequencing (1 MARK)
[1 mark]
e) It allows similarities in amino acid sequences to be compared showing how closely related a species are to improve the process of classification (1 MARK)
[1 mark]
Total for question 3 [10 marks]
Question 4
a) The gill filaments increase the surface area of the gills (1 MARK) allowing more surface for diffusion to occur which makes them a more efficient gas exchange surface (1 MARK)
[2 marks]
b) During inspiration the mouth opens and the buccal cavity floor lowers (1 MARK) increasing the volume and decreasing the pressure forcing air into and over the gills (1 MARK) the mouth closes and the operculum opens (1 MARK) increasing the pressure inside the operculum cavity and causing water to exit through the operculum (1 MARK)
[4 marks]
c) Counter current flow is where water and blood move in opposite directions across the gill plate (1 MARK) This maintains a high concentration gradient for oxygen to diffuse over into the blood/prevents equilibrium from being reached (1 MARK) and allows diffusion to occur over the whole gill plate/lamellae surface which is very efficient (1 MARK)
[3 marks]
d) If the diameter is larger than the surface area to volume ratio would be larger (1 MARK) and thus diffusion would be less efficient and slower (1 MARK)
[2 marks]
e)Less fluid is present in the tracheoles during flight than at rest (1 MARK) This means that during flight gas exchange occurs nearer to the muscle fibres/more gas diffuses closer to the muscle fibres (1 MARK)
[2 marks]
Total for question 4 [13 marks]
Question 5
a)Phloem parenchyma (1 MARK)
Phloem Fibres
[2 marks]
b) 2 features plus explanations must be given for four marks:
Protien filaments in the cytoplasm (1 MARK) allow the bidirectional movement of photosynthates by translocation in the phloem (1 MARK)
No organelles are present (1 MARK) to prevent photosynthates being obstructed during transport (1 MARK)
Sieve plates contain pores allowing photosynthates to move by translocation from source to sink (1 MARK)
[4 marks]
c)Mass flow is the theory that translocation in the phloem is a passive process (1 MARK) The mitochondria produce energy in the form of ATP which moves into the phloem to help translocation occur (1 MARK) this suggests that the process is active and mass flow doesn’t occur (1 mark)
[3 marks]
Total for question 5 [9 marks]
Question 6 (ESSAYS)
Essay A:
ANY 10 POINTS FROM THE LIST BELOW
· CO2 is produced during cellular respiration and when its concentration inside the cell is greater than in the blood it diffuses into the blood
· In the red blood cells CO2 reacts with water to form carbonic acid
· The enzyme that catalyses the reaction is carbonic anhydrase
· Some CO2 reacts with haemoglobin to form carbamino haemoglobin.
· The carbonic acid dissociate into H+ and HCO3- ions
· As the concentration of HCO3- is greater inside the red blood cell that outside the red blood cell it diffuses into the plasma
· HCO3- reacts with NA+ to form sodium hydrogen carbonate
· Inside the red blood cell the PH rises due to acidic H+ ions that react with haemoglobin to form haemoglobinic acid
· Cl- ions enter the red blood cell to restore electrochemical neutrality (chloride shift)
[MAXIMUM 6 MARKS FROM ABOVE]
· When the concentration of oxygen is high the bohr affect occurs
· Meaning that more H+ ions are produced which react with haemoglobin causing the oxgen to dissociate and move into the cell respiring
· Thus the haemoglobin has a lower affinity for oxygen
· Thus the greater the concentration of CO2 produced the more readily oxygen dissociates
· This occurs at respiring tissues during periods of exercise
[MAXIMUM 4 FROM ABOVE]
[10 MARKS]
I cannot remember what the second essay even was so i would need pointers on that if someone would post it below
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FM2002
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#2
the second essay question was describe and explain the structural and functional similarities and differences between the xylem vessels and arteries. I have a feeling I'm one of the few that actually attempted this question?
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aimee2127
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(Original post by Natalierm2707)
BY2 2ND JUNE 2014 UNOFFICIAL MARK SCHEME
I have tried to create a mark scheme similar to ones you would find on exam papers showing you what you usually (and in the past) have got marks for.
This is not set in stone and some of my answers may be incorrect and that is open to discussion, any corrections would be taken willingly, but remember I am just a student like you, I sat this exam for the first time today!
IMPORTANT:
· Words in brackets are not required for the mark
· Words in bold must be present for the mark to be awarded
· the marks for each question will be shown inside [] after each question
· the marks for individual parts of each question will be shown inside () after the marking point has been addressed
· Answers separated by a / mean that either of the words shown are appropriate for the mark
Question 1
a) A = capillaries/capillary network (1 MARK)
B = Epithelial cells/epithelium cells (1 MARK)
C = Lacteal (1 MARK)
[3 marks]
b) (Large/extensive) capillary network inside the villus (1 MARK) (as the products are continually being carried away) creating a large maintained concentration gradient for diffusion of digested substances (1 MARK)
Projections/microvilli from the epithelial cells (1 MARK) Increases the surface area of the villus allowing a greater surface for diffusion of digested substances (1 MARK)
[4 marks]
c) Mucus (1 MARK)
[1 mark]
d) ANY TWO OF: Lubricates the Gut/Traps microorganisms/prevents or protects the gut wall from being digested by digestive enzymes.
[2 marks]
e) The smooth muscle layer contains the (antagonistic pair) of circular and longitudinal muscle (1 MARK) The circular muscle and the longitudinal muscle contract (at different times to eachother) (1 MARK) pushing the digested molecules/bolus along the gut by peristalsis (1 MARK)
[3 marks]
f) An amine group/NH2 is removed from the amino acid (1 MARK) the amine group is converted to urea and the remainder stored as carbohydrate (1 MARK)
[2 marks]
Total for question 1 [15 marks]
Question 2
a) Transpiration is the loss off/diffusion of water vapour (1 MARK) out of the leaf via/through the stomatal pores (into the atmosphere) (1 MARK)
[2 marks]
b) To maintain a transpiration stream (to absorb water into the roots and pull water up the xylem) (1 MARK)
[1 mark]
c) To prevent air from entered the vessels in the leafy shoot (1 MARK) which would have affected the results (1 MARK)
[2 marks]
d) Measure the distance travelled by the air bubble (1 MARK) in a given amount of time (1 MARK)
[2 marks]
e) Xerophyte (1 MARK)
f) Sunken stomata Trap a humid layer of air on the outside of the stomata (1 MARK) which decreases the water potential gradient (1 MARK) preventing more water vapour from exiting the stomata by transpiration (1 MARK)
[3 marks]
g) ANY TWO FROM: Thick cuticle prevents excessive water loss by transpiration/hairs to trap water vapour and decrease the water potential gradient/rolled leaves to reduce the surface area from which transpiration can occur
[2 marks]
Total for question 2 [13 marks]
Question 3
a)Adaptive radiation (1 MARK)
[1 mark]
b)Natural selection shows that there is variation in all species (1 MARK) and that the individuals in a population will compete for food (1 MARK) the better adapted finches with the beak that is suited to that food source will be able to obtain food and survive wheras the less well adapted finches will die (1 MARK) The finches with the well adapted beaks go on to reproduce and create offspring with the same desirable beaks (1 MARK)
[4 marks]
*this question has been highly debated among students as it was very confusing, In the textbook it states that adaptive radiation is the mechanism for natural selection, so natural selection in the context of the birds was what I and most other have gone on to describe as that was the logical answer, whether this is correct or not I don’t know*
c) The more amino acids that two species have in common the more closely related they are (1 MARK) the gorilla and the human have the most number of amino acids in common and thus they are more closely related (1 MARK) than the human and the horse who have less amino acids and common and so are less closely related (1 MARK)
[3 marks]
d) Amino acid sequencing (1 MARK)
[1 mark]
e) It allows similarities in amino acid sequences to be compared showing how closely related a species are to improve the process of classification (1 MARK)
[1 mark]
Total for question 3 [10 marks]
Question 4
a) The gill filaments increase the surface area of the gills (1 MARK) allowing more surface for diffusion to occur which makes them a more efficient gas exchange surface (1 MARK)
[2 marks]
b) During inspiration the mouth opens and the buccal cavity floor lowers (1 MARK) increasing the volume and decreasing the pressure forcing air into and over the gills (1 MARK) the mouth closes and the operculum opens (1 MARK) increasing the pressure inside the operculum cavity and causing water to exit through the operculum (1 MARK)
[4 marks]
c) Counter current flow is where water and blood move in opposite directions across the gill plate (1 MARK) This maintains a high concentration gradient for oxygen to diffuse over into the blood/prevents equilibrium from being reached (1 MARK) and allows diffusion to occur over the whole gill plate/lamellae surface which is very efficient (1 MARK)
[3 marks]
d) If the diameter is larger than the surface area to volume ratio would be larger (1 MARK) and thus diffusion would be less efficient and slower (1 MARK)
[2 marks]
e)Less fluid is present in the tracheoles during flight than at rest (1 MARK) This means that during flight gas exchange occurs nearer to the muscle fibres/more gas diffuses closer to the muscle fibres (1 MARK)
[2 marks]
Total for question 4 [13 marks]
Question 5
a)Phloem parenchyma (1 MARK)
Phloem Fibres
[2 marks]
b) 2 features plus explanations must be given for four marks:
Protien filaments in the cytoplasm (1 MARK) allow the bidirectional movement of photosynthates by translocation in the phloem (1 MARK)
No organelles are present (1 MARK) to prevent photosynthates being obstructed during transport (1 MARK)
Sieve plates contain pores allowing photosynthates to move by translocation from source to sink (1 MARK)
[4 marks]
c)Mass flow is the theory that translocation in the phloem is a passive process (1 MARK) The mitochondria produce energy in the form of ATP which moves into the phloem to help translocation occur (1 MARK) this suggests that the process is active and mass flow doesn’t occur (1 mark)
[3 marks]
Total for question 5 [9 marks]
Question 6 (ESSAYS)
Essay A:
ANY 10 POINTS FROM THE LIST BELOW
· CO2 is produced during cellular respiration and when its concentration inside the cell is greater than in the blood it diffuses into the blood
· In the red blood cells CO2 reacts with water to form carbonic acid
· The enzyme that catalyses the reaction is carbonic anhydrase
· Some CO2 reacts with haemoglobin to form carbamino haemoglobin.
· The carbonic acid dissociate into H+ and HCO3- ions
· As the concentration of HCO3- is greater inside the red blood cell that outside the red blood cell it diffuses into the plasma
· HCO3- reacts with NA+ to form sodium hydrogen carbonate
· Inside the red blood cell the PH rises due to acidic H+ ions that react with haemoglobin to form haemoglobinic acid
· Cl- ions enter the red blood cell to restore electrochemical neutrality (chloride shift)
[MAXIMUM 6 MARKS FROM ABOVE]
· When the concentration of oxygen is high the bohr affect occurs
· Meaning that more H+ ions are produced which react with haemoglobin causing the oxgen to dissociate and move into the cell respiring
· Thus the haemoglobin has a lower affinity for oxygen
· Thus the greater the concentration of CO2 produced the more readily oxygen dissociates
· This occurs at respiring tissues during periods of exercise
[MAXIMUM 4 FROM ABOVE]
[10 MARKS]
I cannot remember what the second essay even was so i would need pointers on that if someone would post it below
1b could you not talk about it being one cell thick?

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koyyj127
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#4
I wrote down soluble food substances are dissolved in the mucus for easy absorption :/
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Ava-
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for 'One benefit of transpiration' do you think that 'it prevents water becoming stagnant' could be a mark?
thanks so much for creating this by the way!
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Higginsy
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1b could I have said 'contain goblet cells to excrete mucus to lubricate the gut'? as a feature of the ileum
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EcstaZEEH
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According to this, I think I got 43/70 so it's a D and one mark of a C...or it can be worse.

Nowadays, I don't have a clue how they mark it anymore...

I never liked BY2...
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Aylaar
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#8
(Original post by EcstaZEEH)
According to this, I think I got 43/70 so it's a D and one mark of a C...or it can be worse.

Nowadays, I don't have a clue how they mark it anymore...

I never liked BY2...
i got 47 I hope they really do lower the grade boundaries! I've messed up by1 too! Its a shame,i really had revised a lot, my current and predicted grades were A for both and WJEC have really let me down
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Babs123
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For the 10 mark question I thought it said the passage of co2 from resourcing tissues to the lungs, so I thought this wasn't to do with chloride shift but instead to do with the passage of co2 in the blood to the lungs? Am I wrong?
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Babs123
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#10
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#10
(Original post by Natalierm2707)
BY2 2ND JUNE 2014 UNOFFICIAL MARK SCHEME
I have tried to create a mark scheme similar to ones you would find on exam papers showing you what you usually (and in the past) have got marks for.
This is not set in stone and some of my answers may be incorrect and that is open to discussion, any corrections would be taken willingly, but remember I am just a student like you, I sat this exam for the first time today!
IMPORTANT:
· Words in brackets are not required for the mark
· Words in bold must be present for the mark to be awarded
· the marks for each question will be shown inside [] after each question
· the marks for individual parts of each question will be shown inside () after the marking point has been addressed
· Answers separated by a / mean that either of the words shown are appropriate for the mark
Question 1
a) A = capillaries/capillary network (1 MARK)
B = Epithelial cells/epithelium cells (1 MARK)
C = Lacteal (1 MARK)
[3 marks]
b) (Large/extensive) capillary network inside the villus (1 MARK) (as the products are continually being carried away) creating a large maintained concentration gradient for diffusion of digested substances (1 MARK)
Projections/microvilli from the epithelial cells (1 MARK) Increases the surface area of the villus allowing a greater surface for diffusion of digested substances (1 MARK)
[4 marks]
c) Mucus (1 MARK)
[1 mark]
d) ANY TWO OF: Lubricates the Gut/Traps microorganisms/prevents or protects the gut wall from being digested by digestive enzymes.
[2 marks]
e) The smooth muscle layer contains the (antagonistic pair) of circular and longitudinal muscle (1 MARK) The circular muscle and the longitudinal muscle contract (at different times to eachother) (1 MARK) pushing the digested molecules/bolus along the gut by peristalsis (1 MARK)
[3 marks]
f) An amine group/NH2 is removed from the amino acid (1 MARK) the amine group is converted to urea and the remainder stored as carbohydrate (1 MARK)
[2 marks]
Total for question 1 [15 marks]
Question 2
a) Transpiration is the loss off/diffusion of water vapour (1 MARK) out of the leaf via/through the stomatal pores (into the atmosphere) (1 MARK)
[2 marks]
b) To maintain a transpiration stream (to absorb water into the roots and pull water up the xylem) (1 MARK)
[1 mark]
c) To prevent air from entered the vessels in the leafy shoot (1 MARK) which would have affected the results (1 MARK)
[2 marks]
d) Measure the distance travelled by the air bubble (1 MARK) in a given amount of time (1 MARK)
[2 marks]
e) Xerophyte (1 MARK)
f) Sunken stomata Trap a humid layer of air on the outside of the stomata (1 MARK) which decreases the water potential gradient (1 MARK) preventing more water vapour from exiting the stomata by transpiration (1 MARK)
[3 marks]
g) ANY TWO FROM: Thick cuticle prevents excessive water loss by transpiration/hairs to trap water vapour and decrease the water potential gradient/rolled leaves to reduce the surface area from which transpiration can occur
[2 marks]
Total for question 2 [13 marks]
Question 3
a)Adaptive radiation (1 MARK)
[1 mark]
b)Natural selection shows that there is variation in all species (1 MARK) and that the individuals in a population will compete for food (1 MARK) the better adapted finches with the beak that is suited to that food source will be able to obtain food and survive wheras the less well adapted finches will die (1 MARK) The finches with the well adapted beaks go on to reproduce and create offspring with the same desirable beaks (1 MARK)
[4 marks]
*this question has been highly debated among students as it was very confusing, In the textbook it states that adaptive radiation is the mechanism for natural selection, so natural selection in the context of the birds was what I and most other have gone on to describe as that was the logical answer, whether this is correct or not I don’t know*
c) The more amino acids that two species have in common the more closely related they are (1 MARK) the gorilla and the human have the most number of amino acids in common and thus they are more closely related (1 MARK) than the human and the horse who have less amino acids and common and so are less closely related (1 MARK)
[3 marks]
d) Amino acid sequencing (1 MARK)
[1 mark]
e) It allows similarities in amino acid sequences to be compared showing how closely related a species are to improve the process of classification (1 MARK)
[1 mark]
Total for question 3 [10 marks]
Question 4
a) The gill filaments increase the surface area of the gills (1 MARK) allowing more surface for diffusion to occur which makes them a more efficient gas exchange surface (1 MARK)
[2 marks]
b) During inspiration the mouth opens and the buccal cavity floor lowers (1 MARK) increasing the volume and decreasing the pressure forcing air into and over the gills (1 MARK) the mouth closes and the operculum opens (1 MARK) increasing the pressure inside the operculum cavity and causing water to exit through the operculum (1 MARK)
[4 marks]
c) Counter current flow is where water and blood move in opposite directions across the gill plate (1 MARK) This maintains a high concentration gradient for oxygen to diffuse over into the blood/prevents equilibrium from being reached (1 MARK) and allows diffusion to occur over the whole gill plate/lamellae surface which is very efficient (1 MARK)
[3 marks]
d) If the diameter is larger than the surface area to volume ratio would be larger (1 MARK) and thus diffusion would be less efficient and slower (1 MARK)
[2 marks]
e)Less fluid is present in the tracheoles during flight than at rest (1 MARK) This means that during flight gas exchange occurs nearer to the muscle fibres/more gas diffuses closer to the muscle fibres (1 MARK)
[2 marks]
Total for question 4 [13 marks]
Question 5
a)Phloem parenchyma (1 MARK)
Phloem Fibres
[2 marks]
b) 2 features plus explanations must be given for four marks:
Protien filaments in the cytoplasm (1 MARK) allow the bidirectional movement of photosynthates by translocation in the phloem (1 MARK)
No organelles are present (1 MARK) to prevent photosynthates being obstructed during transport (1 MARK)
Sieve plates contain pores allowing photosynthates to move by translocation from source to sink (1 MARK)
[4 marks]
c)Mass flow is the theory that translocation in the phloem is a passive process (1 MARK) The mitochondria produce energy in the form of ATP which moves into the phloem to help translocation occur (1 MARK) this suggests that the process is active and mass flow doesn’t occur (1 mark)
[3 marks]
Total for question 5 [9 marks]
Question 6 (ESSAYS)
Essay A:
ANY 10 POINTS FROM THE LIST BELOW
· CO2 is produced during cellular respiration and when its concentration inside the cell is greater than in the blood it diffuses into the blood
· In the red blood cells CO2 reacts with water to form carbonic acid
· The enzyme that catalyses the reaction is carbonic anhydrase
· Some CO2 reacts with haemoglobin to form carbamino haemoglobin.
· The carbonic acid dissociate into H+ and HCO3- ions
· As the concentration of HCO3- is greater inside the red blood cell that outside the red blood cell it diffuses into the plasma
· HCO3- reacts with NA+ to form sodium hydrogen carbonate
· Inside the red blood cell the PH rises due to acidic H+ ions that react with haemoglobin to form haemoglobinic acid
· Cl- ions enter the red blood cell to restore electrochemical neutrality (chloride shift)
[MAXIMUM 6 MARKS FROM ABOVE]
· When the concentration of oxygen is high the bohr affect occurs
· Meaning that more H+ ions are produced which react with haemoglobin causing the oxgen to dissociate and move into the cell respiring
· Thus the haemoglobin has a lower affinity for oxygen
· Thus the greater the concentration of CO2 produced the more readily oxygen dissociates
· This occurs at respiring tissues during periods of exercise
[MAXIMUM 4 FROM ABOVE]
[10 MARKS]
I cannot remember what the second essay even was so i would need pointers on that if someone would post it below


For the 10 mark question I thought it said the passage of co2 from resourcing tissues to the lungs, so I thought this wasn't to do with chloride shift but instead to do with the passage of co2 in the blood to the lungs? Am I wrong?
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reconn
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#11
Good work.

I think you mean SA:Vol decreases here:

d) If the diameter is larger than the surface area to volume ratio would be larger (1 MARK) and thus diffusion would be less efficient and slower (1 MARK)
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Aylaar
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#12
(Original post by Babs123)
For the 10 mark question I thought it said the passage of co2 from resourcing tissues to the lungs, so I thought this wasn't to do with chloride shift but instead to do with the passage of co2 in the blood to the lungs? Am I wrong?
I wrote about the chloride shift for the first half but all the brainy people in my school wrote about the heart, so u have no idea. On here they're saying it's the chloride shift but the majority in my school wrote about the heart
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Nasivad
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Thanks for the mark scheme
I was wondering if anyone knows if I would still get a mark if for question 1D, I put that the gut wall is protected, but I didn't mention enzymes. Also for question 2G, I put that the leaf is rolled to protect the stomata from factors, such as sunlight and wind, that could cause transpiration.
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Rachel9616
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I wrote about the passage way through the heart and then also the chloride shift but some people in my school wrote about the lymphatic sustem etc. ? 😱
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EcstaZEEH
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#15
(Original post by Aylaar)
i got 47 I hope they really do lower the grade boundaries! I've messed up by1 too! Its a shame,i really had revised a lot, my current and predicted grades were A for both and WJEC have really let me down
MARK SCHEMES are out! 43 is a B (3 marks shy of A)

47 is an A grade!
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